1. Field of the Invention
The present invention relates to a golf club and a method of producing the same. More particularly, the present invention relates to a golf club having a hollow iron clubhead with a hollow therein that is produced mainly by forging and welding. The present invention also relates to a method of producing the golf club.
2. Discussion of Related Art
There is publicly known a method of producing a hollow iron clubhead as follows. A front part including a face and a rear part including a sole are produced as two split parts by forging using a press or the like, and the two parts are welded together to form a hollow iron clubhead, followed by pouring a molten metal into the hollow inside of the clubhead to fill the hollow (for example, see Japanese Patent Application Post-Examination Publication No. Sho 39-21879). There has also been proposed a method of producing a wood golf club, wherein a wood clubhead comprises two parts, i.e. a front part including a face, and a rear part including a sole, and the two parts are integrally welded together with a pipe for mounting a clubshaft (for example, see Japanese Utility Model Application Post-Examination Publication No. Sho 61-33971).
However, the face and the sole require different constituent materials because they are required to perform different functions. For example, the face is a surface for striking a golf ball and hence requires a metallic material capable of exhibiting excellent impact resistance and generating high restitution. If the face part is made of the same kind of metallic material as that used to constitute the sole part, it is necessary to partially increase the wall thickness. Under certain circumstances, a different kind of metal, e.g. pure titanium, is clad to the clubface surface to increase the coefficient of restitution, and the metal-clad face part and the sole part are joined together to form a clubhead. In these cases, the wall thickness of the face part is different from that of the main body part.
Meanwhile, iron clubheads are demanded to have as low a center of gravity as possible from the viewpoint of stability in striking performance. In this regard, if the above-described clubhead producing method using two split parts formed by forging is employed to produce a hollow iron clubhead having the above-described face, the center of gravity cannot be lowered as desired. That is, because the face has an increased wall thickness, if a front part including the face is produced, the overall weight increases, resulting in an undesirably high center of gravity.
Accordingly, the conventional method of producing a clubhead from two split parts is not suitable for producing a hollow iron clubhead having as low a center of gravity as possible. Further, the lower portion of a hosel, which is a part for securing one end of the shaft of an iron golf club is generally a solid structure. Therefore, even if attempts are made to design the iron clubhead so that the center of gravity is lowered, there is a limit to the creation of a lower center of gravity.
The present invention was made in view of the above-described technical background. Accordingly, the present invention attains the following objects.
An object of the present invention is to provide a golf club designed to create a low center of gravity and to allow the center of gravity to be set at any desired position in the longitudinal direction of the clubhead, and also provide a method of producing the golf club.
Another object of the present invention is to provide a golf club enabling free selection of a material for the clubface to rebound a golf ball, and also provide a method of producing the golf club.
Still another object of the present invention is to provide a golf club that is easy to manufacture and a method of producing the golf club.
To attain the above-described objects, the present invention provides a golf club having a hollow iron clubhead with a hollow therein. The golf club includes a clubface member having a striking face for striking a golf ball. A front body member is integrally welded to the clubface member to constitute a front body portion of the hollow iron clubhead. The front body member has a first hosel portion for forming a tubular hosel communicating with the hollow. A rear body member is integrally welded to the front body member to constitute a rear body portion of the hollow iron clubhead. The rear body member has a second hosel portion for forming the tubular hosel in combination with the first hosel portion.
Preferably, the first hosel portion and the second hosel portion are half hosel portions, respectively. Each half hosel portion has a shape formed by cutting a cylinder along a plane containing a center axis thereof. The half hosel portions are welded together to form the hosel for securing one end of a golf clubshaft.
Further, the clubface member is preferably positioned in a through-hole formed in the front body member and welded to the front body member. Preferably, a weight member is secured to the bottom of the rear body member by welding. Preferably, the clubface member is different in constituent material from the front body member. Preferably, a cylindrical member for securing one end of a golf clubshaft is joined to the hosel by welding.
In addition, the present invention provides a method of producing a golf club having a hollow iron clubhead with a hollow therein. According to the golf club producing method, a sheet material is cut to form a clubface member having a striking face for striking a golf ball. A sheet material is subjected to press working to form a front body member that is to be integrally welded to the clubface member to constitute a front body portion of the hollow iron clubhead. The clubface member and the front body member are integrally welded together. A sheet material is subjected to press working to form a rear body member that is to be integrally welded to the front body member to constitute a rear body portion of the hollow iron clubhead. The front body member, which has been integrally welded with the clubface member, and the rear body member are integrally welded together to form the hollow iron clubhead.
Preferably, the golf club producing method according to the present invention is carried out as follows. A clubface blank for forming the clubface member is prepared by blanking. A front body blank for forming the front body member is prepared by blanking. The clubface blank and the front body blank are integrally joined together by welding. The integral assembly of the front body blank and the clubface blank is drawn to form the front body member. A rear body blank for forming the rear body member is prepared by blanking. The rear body blank is drawn to form the rear body member. The front body member and the rear body member are integrally joined together by welding.
Preferably, a through-hole is formed in the front body blank by punching, and the clubface member is positioned in the through-hole and welded to the front body member.
Preferably, the drawing performed on the clubface blank, the front body blank and the rear body blank is hot working in which a material is drawn under heating to not less than the recrystallization temperature of the material.
Preferably, the front body blank and the rear body blank have respective half hosel portions for forming in combination a hosel for securing one end of a golf clubshaft. Each half hosel portion has a shape formed by cutting a cylinder along a plane containing a center axis thereof.
Preferably, a cylindrical member for securing one end of a golf clubshaft is joined to the hosel by welding.